That is not entirely correct. Swoole already takes away a lot of the CPU heavy code, like HTTP protocol parsing by providing it in its C extension.

For one of my PHP extensions I benchmarked the C level implementation to be 5x faster than Jitted PHP code: https://beberlei.de/2019/03/25/the_jit_in_relation_to_php_ex...

So no, if your Swoole application does a lot of async I/O and its only in CPU code to delegate between I/O, then it will not benefit from the JIT.

"Long-Running process" alone doesn't mean that its CPU bound.